Echo Base - a new PT2399 delay

[omarvolta]

by short out do you mean simply lifting one leg of the cap(1uf) or to bridge both legs together(so that both pins 1 and 2 bridge)??

[slacker]

Just bridge pins 1 and 2 together.

[omarvolta]

got it, thank you very much!

[jmasciswannabe]

Built it and sounds great. I dig the lfo better than the commonsound add on one. I'll have to try the waveshaper mod. I used the anonymousface layout. For some reason i thought all the ics faced the same direction and fried one of the tl072s. Better that than the pt2399! So be careful! Anyway, I am in the process of boxing this up and have got a rad graphic and plan on clearcoating it. I would like to keep it true to the original and call it ECHO BASE in the same font thats on the schematic. Anyone know the font name?

Thanks for a fun build slacker and anonymousface!!

[slacker]

Cheers, I can't remember what the font is called off the top of my head. I've still got it on my PC so I'll have a look for it later..

[jmasciswannabe]

Thanks, I'll be sure to check back.

[slacker]

It's called checkbook, I think I got it from here http://www.1001freefonts.com/checkbook.htm.

[omarvolta]

ok, i'm back with just one more question. Since the wet signal is being mixed to the dry signal via the volume pot, how could I add a pot to control the volume of only dry signal?? can it be done??

[jmasciswannabe]

I believe you can control the dry volume by wiring up a pot for the 10k resistor between pin 1 and pin 6 of the u3 TLO72. Slacker, thanks for the font!

[slacker]

Yeah that would work, putting say a 100k pot in series with the 10k would let you reduce the dry level. If you also changed the 10k to a smaller value that would let you increase the dry volume.
The only problem with doing this is that the dry signal is present when the effect is bypassed so the dry volume pot would affect the bypassed volume. There's no easy way to change the dry volume only when the effect is engaged.

[loss1234]

of course, you could hook up a volume pot mod so you could control the mix in realtime, and then put it back to 10 for the bypass.

right?

[slacker]

Thinking about it, if you put a pot in series with the 10k resistor as mentioned above you could then use a switch to short out the pot when you bypass the effect that would return the volume level to unity.
You could do this by using a DPDT switch for the bypass switch and use the spare halve to short out the pot.

[omarvolta]

great! i'll give it a try then and see how it works out. thanks a lot!

[Valoosj]

Hey Ian

Beginning of Juli I'm going to try the extra time mod, and let you know how it works out.
In the meantime I was thinking that it might come handy if you were to make a settings list on how to get the chorus, pitch bending,...
After listening to the clips in the first post and on page two I wonder how you are able to get all these nice sounds.

[soggybag]

I have been meaning to build the Echo Base for a while now. I just started last night. I'm using Junkworks layout here: http://blogs.yahoo.co.jp/anonymousfacelesscoward/19192939.html

[Valoosj]

I'll be using that same layout. It's postponed until my exams are finished though.

[Tuemmueh]

Hi there,

sorry, but I'm not able to understand all the tone-filtering and shaping in this circuit, maybe someone can point me to the parts where most of the filtering is done so I might to experiment with tone-controll for the delays?!

Thanks,
Timm

[Dimitree]

Hi..it is possible to add a loop send-return between the 20K resistor and the 100n cap across the pin 2 of the feedback pot? In this way, connecting an effect in this loop, this effects influences the repeats always more..right? If we use, for example, an octave up in the loop, the first repeat would be 1oct up, the second would be 2oct up, etc.. (obviously the feedback pot should be set low, with a few of repeats, otherwise the pitch grow to much)

Another question: why there are 2 1N4148 across the feedback pot?

thanks so much!
Dimitri

[slacker]

Adding a send return where you've suggested would work fine. You might want to add a buffer to the return and possibly one to the send but it will probably be fine without any.
The diodes don't really do anything unless you turn the feedback pot up very high then they clip the signal and stop the repeats getting too loud. The pedal will still do the usual feedback sounds you get from delays but the volume stays at a more usable level.

[gutsofgold]

The diodes don't really do anything unless you turn the feedback pot up very high then they clip the signal and stop the repeats getting too loud. The pedal will still do the usual feedback sounds you get from delays but the volume stays at a more usable level.

I added a "feedback" switch and pot to my Rebote 2, could I also put two diodes on the pot as you did here to control the high volume with feedback?

Here is how I have it wired up...
http://i27.photobucket.com/albums/c153/kahelia/pedalia/Dealy_mom_feedback.jpg